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Hugh Pickens writes "Caltech and the University of California have been making progress toward the development and construction of the Thirty-Meter Telescope (TMT) with the recent $200 million commitment from the Gordon and Betty Moore Foundation. The core of the TMT Observatory will be a wide-field, alt-az Ritchey-Chretien telescope with a 492 segment, 30 meter diameter primary mirror, a fully active secondary mirror and an articulated tertiary mirror. TMT will be the first ground-based astronomy telescope designed with adaptive optics as an integral system element that will sense atmospheric turbulence in real-time, correct the optical beam of the telescope to remove its effect, and enable true diffraction-limited imaging on the ground. TMT will have 144 times the collecting area of the Hubble Space Telescope and a spatial resolution at near-infrared and longer wavelengths more than ten times better, equivalent to observing above the Earth's atmosphere for many observations at a fraction of the cost of a space-based observatory. TMT will reach further and see more clearly than previous telescopes by a factor of 10 to 100 depending on the observation and will be a fundamental tool for the investigation of large-scale structure in the young universe including the era in which most of the stars and heavy elements were formed."

All that fancy schmancy adaptve optics will still suck when it's raining.It doesn't rain very often in West Texas. If you made your snarky comment out of a misguided need to defend the Hubble, you should have mentioned UV or other frequencies you can't image from the ground.

Did you REALLY miss the humor in my remark? or were you trolling?

I'm impressed as hell with the adaptive optics in the new Scope. Adjusting for turbulence and refraction is impressive all by itself, doing it realtime is just short of magic.

I predict they'll find out that all the stars in the galactic core went nova some millions of years ago in a vast chain reaction... and that the resulting blast wave will reach Earth about 30,000 years from now. Better start looking around... I hear real estate in the Lesser Magellanic Cloud is a good buy this time of year.

Well, the Rooskies didn't have "Progress" then, but I worked at a DoD observatory where that was exactly what we did. Meaning, we geared up the 'scopes to watch the Russian & Chinese spacecraft (and, maybe, 'illuminate' them once in a while, or bounce a laser off the reflectors WE left on the moon).

You didn't need a 30 meter telescope to look at something only 90 miles away--straight up! Can't really mention which 'scopes but there are images of them on the web. They watched Kosmonauts working outside

As compared to what? The Large Hadron Collider? The Supercollider? How about the Titanic or the Great Wall of China?

I happen to like these names. This is astronomy. The study of very large, huge, colossal, inconceivably gigantic structures and scales. It's very much like the exponential growth in the size of electronic storage devices. I get a similar feeling when I ponder these concepts.

If you follow the development of modern telescopes, they are in fact quite descriptive, in a relative way. If you're

Seems like someone is trying hard to overcompensate some inadequacy..."Why yes, I DO operate the Ginormousely Absurd You-Can't-Believe-How-Fucking-Huge-It-Is Oversized-By-Any-Reasonable-Standard-Of-Measurement-And-By-Most-Unreasonable-Ones-As-Well Motherfucking Large Telescope"

yes, but then every field has it's own set. Electronics for example has - Large Scale Integration, Very Large Scale Integration, then the new one seems to be Ultra Large Scale Integration. I mean come on... , let them have their fun.

No, No thats not how it works. Their names are irrelevant its the acronyms that matter - its VLT, GMT, ELT and OWL (like the bird). There is also MMT (was multiple mirror - then became Monolithic Mirror) LSST, PS1, LBT, and the TMT - I don't remember when the last time I heard people refer to any of these by their full names (very few exceptions and most of those are like the - like CTIO 4m or just a name like Magellan - which is two telescopes the Clay and Baade - the GMT you complain about is going righ

Yes, you are quite right, except there is already a dog fight between Twenty Metre Telescope and Ten Metre Telescope to register for the acronym TMT, so, glad you quit the the party of idiocy and warm welcome to the party of ambiguity

I know an engineer working on this project who jokes that "Thirty Meter Telescope" is a good name because if funding is cut they can downscope to the "Twenty Meter Telescope" without having to change any of the "TMT" logos.

With all due respect, this will be the most important school ever built to date when it is up and running, it has many times the potential in terms of a Hubble comparison. I tip my hat to Gordon Moore, and might even have an intel cpu in the next computer I build.

Schools teach a pretty fixed view of things and move forward at agonizingly slow speeds in their curriculum choices. Building more schools is an admirable effort, but this has the potential fo

TMT will be the first ground-based astronomy telescope designed with adaptive optics as an integral system element that will sense atmospheric turbulence in real-time, correct the optical beam of the telescope to remove its effect, and enable true diffraction-limited imaging on the ground.

with the adaptive optics capability of the quite beautiful HET [utexas.edu] at McDonald Observatory? I suppose with any number of very specific qualifiers, one could claim to be "first".

What is the difference between the TMT and the HET with regards to "adaptive optics" and being able to negate the effects of atmospheric turbulence in real time (which the HET can do)?

BTW, if you ever have the chance, the McDonald Observatory in Ft. Davis, TX is well worth the trip!

/.ers really need to work on their moderation skills. How on earth did my post get modded +2 Interesting?!? It was a stupid joke about Texas, a place I'd never even been to! I'd request that someone give it a -1 Overrated, but we all know what happens to "please mod me down" posts in these parts.

Can someone in the know reconcile this statement:What is the difference between the TMT and the HET with regards to "adaptive optics" and being able to negate the effects of atmospheric turbulence in real time (which the HET can do)?

It is all a question of scale. Correcting a 30m telescope is harder than correcting for a 9m telescope (larger pupil = more atmospheric aberration over it = higher resolution requirements on your wavefront sensor, and more degrees of freedom on your deformable mirrors). There is also the question of the level of correction. Neither telescope can correct all turbulence from all conjugates and angles perfectly in realtime. The scale of the residual is what ultimately determines the performance of your system. (In fact, there are a few effects dealing with the angular separation of the laser guide star and the edge of your telescope pupil that make correction for larger telescopes intrinsically more challenging). In short, the adaptive optics required to correct a 30meter telescope are quite a bit "harder" than those required for a 10m telescope, and the technologies being developed for the TMT are really pushing the envelope of current AO technology.

It actually doesn't even have an imager, just spectrographs. The term "adaptive optics" refers specifically to systems where a mirror in the light path deforms at very high rates (50-2000 Hz) to correct atmospheric distortions in the wavefront of the incoming light. TMT will have this, as do the VLT, Keck, Gemini, MMT, and Palomar. TMT is just the first that is being designed from the ground up with AO in mind.

Hobby Eberly is basically a very low-budget version of telescopes like Keck. It has the same mirror size (and therefore the same light collecting ability), but they made several design compromises to knock the cost down from $100 million (for Keck) to about $15 million. Most of these compromises reduce the image quality, so they don't even bother trying. They just mounted a bunch of spectrographs since somebody taking a spectrum of a single object usually doesn't care about the nonplanar focal surface and correspondingly tiny effective field of view.

by trying things other than ridiculous expensive space experiments. Now I hope they just please recruit some of the scientists away from super-collider projects. So I can sleep at night without dreams of black holes forming up through my garbage disposal.